Quinolones and Steroids Significantly Increase Risk of Deep Tendon Rupture

Risk Quantification

The combination of quinolones and corticosteroids dramatically increases the risk of tendon rupture, with an odds ratio of 43.2 (95% CI, 5.5-341.1) specifically for Achilles tendon rupture compared to fluoroquinolone use alone 1, 2, 3
Fluoroquinolones alone increase the risk of tendon disorders (odds ratio 1.7), tendon rupture (odds ratio 1.3), and specifically Achilles tendon rupture (odds ratio 4.1) 1, 2, 3
When fluoroquinolones are combined with corticosteroids, the risk increases dramatically for both tendon rupture (odds ratio 3.1) and specifically Achilles tendon rupture (odds ratio 43.2) 1, 2, 3
The absolute increase in risk is about 12 cases of Achilles tendon rupture per 100,000 persons within 90 days of fluoroquinolone treatment 1, 4

Age over 60 years significantly increases risk, with 4 times higher risk of Achilles tendon rupture compared to the general population 1, 4
When stratified by age, 1 Achilles tendon rupture per 1,638 fluoroquinolone-treated patients older than 60 years could be expected 1, 3
Participation in sports is associated with a higher risk of tendon disorders, with 50% of tendon disorders in fluoroquinolone users occurring during sports participation 3

Symptoms typically occur within 1 week of exposure to fluoroquinolones (median 6 days) 1, 4
The risk is highest within the first 30 days following exposure to fluoroquinolones 3
In rare cases, symptoms can appear as early as 2 hours after initial exposure or as late as 6 months after discontinuation 4

While the Achilles tendon is most commonly affected (90% of cases), other tendons may also be involved 1, 4
Other affected tendons include patellar tendon, rotator cuff, common flexor and extensor tendons at the elbow 5
In more than half of Achilles tendon cases, both tendons are affected bilaterally 5

Consider magnesium supplementation during fluoroquinolone treatment if no contraindications exist 6
For high-risk individuals (over 60 years, history of tendon disorders, athletes), consider alternative antibiotic classes when clinically appropriate 6
Avoid unnecessary physical activity, particularly sports participation, during fluoroquinolone treatment, especially in high-risk individuals 3